NanoPC-T4 RK3399：uboot cmd与boot加载

一：获取autoboot命令

命令行模式的主逻辑接口：

#uboot_dev/common/main.c
 
/* We come here after U-Boot is initialised and ready to process commands */
void main_loop(void)
{
	const char *s;
 
	bootstage_mark_name(BOOTSTAGE_ID_MAIN_LOOP, "main_loop");
 
    ...
 
	s = bootdelay_process();
	if (cli_process_fdt(&s))
		cli_secure_boot_cmd(s);
	printf("[DEBUG]: s:%s\n",s);
	autoboot_command(s);
 
	cli_loop();
	panic("No CLI available");
}

通过env_get获取autoboot命令字符串s：

#uboot_dev/common/autoboot.c
 
const char *bootdelay_process(void)
{
	char *s;
	int bootdelay;
 
	bootcount_inc();
 
	s = env_get("bootdelay");
	bootdelay = s ? (int)simple_strtol(s, NULL, 10) : CONFIG_BOOTDELAY;
 
...
 
#ifdef CONFIG_POST
	if (gd->flags & GD_FLG_POSTFAIL) {
		s = env_get("failbootcmd");
	} else
#endif